Sunnybrook Health Sciences Centre

About: Sunnybrook Health Sciences Centre is a healthcare organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Breast cancer. The organization has 7689 authors who have published 15236 publications receiving 523019 citations. The organization is also known as: Sunnybrook.

Impacts of COVID-19 on Youth Mental Health, Substance Use, and Well-being: A Rapid Survey of Clinical and Community Samples: Repercussions de la COVID-19 sur la sante mentale, l'utilisation de substances et le bien-etre des adolescents : un sondage rapide d'echantillons cliniques et communautaires

Abstract: Objectives:The current novel coronavirus disease of 2019 (COVID-19) pandemic presents a time-sensitive opportunity to rapidly enhance our knowledge about the impacts of public health crises on yout...

A cross-country comparison of intensive care physicians’ beliefs about their transfusion behaviour: A qualitative study using the theoretical domains framework

Abstract: Background: Evidence of variations in red blood cell transfusion practices have been reported in a wide range of clinical settings. Parallel studies in Canada and the United Kingdom were designed to explore transfusion behaviour in intensive care physicians. The aim of this paper is three-fold: first, to explore beliefs that influence Canadian intensive care physicians’ transfusion behaviour; second, to systematically select relevant theories and models using the Theoretical Domains Framework (TDF) to inform a future predictive study; and third, to compare its results with the UK study. Methods: Ten intensive care unit (ICU) physicians throughout Canada were interviewed. Physicians’ responses were coded into theoretical domains, and specific beliefs were generated for each response. Theoretical domains relevant to behaviour change were identified, and specific constructs from the relevant domains were used to select psychological theories. The results from Canada and the United Kingdom were compared. Results: Seven theoretical domains populated by 31 specific beliefs were identified as relevant to the target behaviour. The domains Beliefs about capabilities (confident to not transfuse if patients’ clinical condition is stable), Beliefs about consequences (positive beliefs of reducing infection and saving resources and negative beliefs about risking patients’ clinical outcome and potentially more work), Social influences (transfusion decision is influenced by team members and patients’ relatives), and Behavioural regulation (wide range of approaches to encourage restrictive transfusion) that were identified in the UK study were also relevant in the Canadian context. Three additional domains, Knowledge (it requires more evidence to support restrictive transfusion), Social/professional role and identity (conflicting beliefs about not adhering to guidelines, referring to evidence, believing restrictive transfusion as professional standard, and believing that guideline is important for other professionals), and Motivation and goals (opposing beliefs about the importance of restrictive transfusion and compatibility with other goals), were also identified in this study. Similar to the UK study, the Theory of Planned Behaviour, Social Cognitive Theory, Operant Learning Theory, Action Planning, and Knowledge-Attitude-Behaviour model were identified as potentially relevant theories and models for further study. Personal project analysis was added to the Canadian study to explore the Motivation and goals domain in further detail. (Continued on next page)

Lack of association between outcome measures of nerve regeneration.

Abstract: Studies of nerve regeneration in rodents utilize at least one of three classes of outcome measures: electrophysiology, morphometry, and functional tests. The assumption that these measures are correlated was tested utilizing a data set of 16 variables. Significant correlations (Spearman's rho, P ⩽ 0.05) were found within variable classes; however, none were found between classes. The three commonly utilized outcome measures do not measure the same phenomenon but rather discrete aspects of nerve regeneration. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:1095–1097, 1998.

Molecularly targeted gold nanoparticles enhance the radiation response of breast cancer cells and tumor xenografts to X-radiation

Abstract: The purpose of this study was to evaluate the effect of molecularly targeted gold nanoparticles (AuNPs) on tumor radiosensitization both in vitro and in vivo. Human Epidermal Growth Factor Receptor-2 (HER-2)-targeted AuNPs (Au–T) were synthesized by conjugating trastuzumab (Herceptin) to 30 nm AuNPs. In vitro, the cytotoxicity of Au-T or non-targeted AuNPs (Au–P) was assessed by γ-H2AX immunofluorescence microscopy for DNA damage and clonogenic survival assays. In vivo, athymic mice bearing subcutaneous MDA-MB-361 xenografts were treated with a single dose of 11 Gy of 100 kVp X-rays 24 h after intratumoral injection of Au–T (~0.8 mg of Au) or no X-radiation. Normal tissue toxicity was determined by hematology or biochemistry parameters. The combination of Au–P or Au–T with X-ray exposure increased the formation of γ-H2AX foci by 1.7 (P = 0.054) and 3.3 (P = 0.024) fold in comparison to X-radiation alone, respectively. The clonogenic survival of cells exposed to Au–T and X-rays was significantly lower from that of cells exposed to X-radiation alone, which translated to a dose enhancement factor of 1.6. In contrast, survival of cells exposed to Au–P and X-rays versus X-radiation alone were not significantly different. In vivo, the combination of Au–T and X-radiation resulted in regression of MDA-MB-361 tumors by 46 % as compared to treatment with X-radiation (16.0 % increase in tumor volume). No significant normal tissue toxicity was observed. Radiosensitization of breast cancer to X-radiation with AuNPs was successfully achieved with an optimized therapeutic strategy of molecular targeting of HER-2 and intratumoral administration.

Measuring injury severity: time for a change?

Abstract: Background: The Injury Severity Score (ISS) does not take into account multiple injuries in the same body region, whereas a New ISS (NISS) may provide a more accurate measure of trauma severity by considering the patient's three greatest injuries regardless of body region. The purpose of this study was to evaluate the ISS and NISS in patients with blunt trauma. Methods: Consecutive individuals treated from January of 1992 to September of 1996 at one institution were included if they had sustained blunt trauma and satisfied triage standards (n = 2,328). For each patient, we computed the ISS and the NISS to determine how often the two scores were identical or discrepant. Discrepant cases were then further analyzed using receiver operating characteristic curves to determine which score better predicted short-term mortality. Results: The mean ISS was 25 ± 13, and the mean NISS was 33 ± 18. The two predictive scores were identical in 32% of patients and discrepant in 68% of patients. Patients with identical scores had a lower mortality rate than patients with discrepant scores (10% vs. 13%; p < 0.02). In patients with discrepant scores, the area under the receiver operating characteristic curves was greater for the NISS than the ISS (0.852 vs. 0.799; p < 0.001), and greater amounts of discrepancy were associated with increasing rates of mortality (p < 0.001). Conclusions: The NISS often increases the apparent severity of injury and provides a more accurate prediction of short-term mortality. The benefit associated with using the NISS rather than the ISS must be weighed against the disadvantages of changing a scoring system and the potential for still greater improvements.